- Email: [email protected]
Effect of iloprost on plasma levels of serotonin and asymmetrical dimethylarginine, and on platelet levels of serotonin in patients affected by peripheral arterial occlusive disease
300
XVIII S.I.S.A. National Congress The relationship between BMI and common carotid plaques or Apo B and bifurcation plaques are independent of hs-CPR concentration: findings from Progetto ATENA. *G. lannuzzo, *M. Gentile, *F. Faccenda, ^F. Rubba, *A. Giannino, *S. Panico, *E. Celentano, *M. De Michete, *P. Rubba. *Dipartimento Medicina Clinica Sperimentale, Universit~l Federico II, Napoli, Italy, ^Direzione Sanitaria A.U.P., Universita Federico II, Napoli, Italy. The relationship between BMI and common carotid plaques or Apo B and bifurcation plaques has been evaluated in a population-based cohort study in women, aged 30-69, living in the metropolitan area of Naples, Southern Italy (Progetto ATENA). Serum cholesterol, HDL-cholesterol, LDL-cholesterol, Triglyceride, Insulin, HOMA, Apo B and hs-CPR are measured in 390 women, as a part of 5.062 In this group carotid ultrasound examination (B-Mode imaging) was performed in 3 sites for each artery, and prevalence at carotid sites of increased intima-media thickness IMT and/or plaque ( I M T > l m m ) was calculated. The association between IMT, BMI, Apo B and hs-CRP has been evaluated taking into account different adjustment models. Women in the second and third tertile of BMI, compared with those in the first tertile, show the following OR of having increased IMT at common carotid site: II vs I tertite 1.9 (p=0.02), III vs I tertile 2.1 (p=0.01); adjusted for age, apoB tertUes and hs-CPR. Women in the second and third tertile of Apo B, compared with those in the first tertile, show the following OR of having increased IMT at bifurcation carotid site: II vs I tertile 1.7 (p=0.05), Ill vs I tertile 2 (p=0.01); adjusted for age, BMI tertiles and hs-CPR. Hs-CPR does not contributes significantly to the models either as continuous or categoric variable. These findings show that relationship between BMI and common carotid plaques or Apo B and bifurcation plaques are independent of hs-CPR concentration.
STEROL 27-HYDROXYLASE IS REGULATED BY INFLAMMATORY STIMULI IN MONOCYTE-MACROPHAGES F. Gilardi, A. Vigil1, N. Mitro, M Crestani, D. Caruso G. Galli and E. De Fabiani Dip. Scienze Farmacologiche, Milano, Italy, 1Dep. Bioquimica, Granada, Spain There is a link between inflammation and diseases characterized by abnormal lipid storage. As modulators of lipid metabolism and immune responses, macrophages play a central rote in the atherogenic process. In macrephages sterol 27-hydroxylase (CYP27) initiates the conversion of cholesterol to more polar metabolites that are less prone to be stored within the cell. Therefore the level of CYP27 expression may have important effects on cholesterol loading and, in turn, on the inflammatory potential of macrophages. The aim of our study was to explore the role of tumor necrosis factor a (TNF--a) on CYP27 in human monocytemacrophages. We found that TNF-a induces the expression of NF-KBregulated genes and also stimulates CYP27 mRNA in PMAdifferentiated THP-I. Other genes involved in cholesterol efflux are not affected. In kinetic studies we observed that CYP27 is upregulated only after 4-24 h exposure to TNF-a. Experiments with protein synthesis inhibitors provided evidence that the mechanism by which TNF-c~ upregulates CYP27 requires newly synthesized protein factors. By transient transfections of undifferentiated THP-1, in which CYP27 is expressed at very low levels, treatment with TNF-e led to a significant but mild stimulation of the human CYP27 promoter. These results suggest that TNF-a may potentiate CYP27 expression only when the gene is already transactivated, as it occurs in mature macrophages. Our findings support the concept that CYP27 gene may be part of the inflammatory response in macrophages thus acting as a link between inflammation and lipid metabolism. A. Vigil is a fellow supported by a Marie Curie training program (EC)
15-1ipoxygenase modified LDL induce endothelial dysfunction in HUVEC A. Reduzzi, A. Pirillo, H.Kuehn, A.L. Catapano Dipartimento di Scienze Farmacologiche, Universit~ di Milano The oxidative modification of LDL contributes to atherogenesis and several evidences suggest that 15- lipoxygenase, an enzyme expressed in atherosclerotic lesions, may play a role in this process. In this work we aimed at investigating the role of 15-1ipoxygenase modified LDL (15Io/LDL) as determined by the modulation of gene transcription and protein expression during the atherogenic processes. In vitro experiments in human endothelial cells reveal that the lipoprotein modified by 15-1ipoxygenase is less associated to cells as compared to native LDL, and that this reduction is related to the extent of LDL modification (LDL =50.4%+1.04%, 15-1o/LDL 24h = 40.8%+ 4.8%,15Io/LDL 72h =17.5%+ 3.5%). In spite of their reduced ability to interact with cells, 15-1o/LDL interfere with cellular functions by modulating inflammatory mechanisms. Real time-PCR and citofluorimetry studies demonstrated that 15-1o/LDL stimulate the expression of adhesion molecules (ICAM-1) both at transcriptional and translational level, in addition incubation with 15-1o/LDL induced a higher oxidative stress in endothelial cells (%positive events:15-1o/LDL 24h= +26%,15-1o/LDL 72h= +23%, compared to native LDL). Furthermore the expression of mRNA for LOX-1, an endothelial lipoprotein receptor involved in the development of atherosclerosis, was induced after incubation with 15Io/LDL, ad demonstrated by RT-PCR (LDL =1.8+0.6, 15-LDL 24h =2.6:t:0.4, 15-LDL 72h =2.6+0.6 fold). These data suggest that 15lipoxygenase may promote atheroscleresis altering endothelial function, and underline the importance of this enzyme in inflammatory processes.
EFFECT OF ILOPROST ON PLASMA LEVELS OF SEROTONIN AND ASYMMETRICAL DIMETHYLARGININE, AND ON PLATELET LEVELS OF SEROTONIN IN PATIENTS AFFECTED BY PERIPHERAL ARTERIAL OCCLUSIVE DISEASE Blardi P. *, de Lalla A. *, Pieragalli D.*, De Franco V.*, Meini S.*, Ceccatelli L. *, Auteri A. * Centro di Farmacologia Clinica , Dipartimento di Medicina Clinica e Scienze Immunologiche, Sezione di Medicina Interna*, Universit~ degli Studi di Siena Iloprost, a stable prostacyclin analogue, is used in the treatment of peripheral arterial occlusive disease (PAOD). We investigated the effect of iloprost on peripheral markers of endothelial dysfunction, such as plasma asymmetrical dimethylarginine (ADMA) and plasma and platelet serotonin (5-HT). ADMA is an endogenous inhibitor of nitric oxide synthase, normally present in human plasma. Elevation of ADMA has been associated to impaired endothelium-dependent vasodilation and hyperaggregability of platelets. 5-HT is derived by the aminoacid trypthophan. Synthesized in enterochromaffin cells, 5-HT is released into blood, incorporated in platelets and stored in dense granules. At the site of endothelial lesions, platelets aggregate and release 5-HT that is able to induce vasoconstriction and aggregation of platelets in presence of endothelial injury and mitogenesis of arterial smooth muscle cells and endothelial cells. We investigated the effect of Uoprest on plasma levels of ADMA, as well as on plasma and platelet levels of 5-HT, in patients with PAOD (Fontaine stage III and IV). Twelve patients (9 men and 3 women, mean age 77 + 7.3 years) were included in the study. They were treated with intravenous iloprost (1.5 ng/kg/min) for 16 hours a day for 7 consecutive days. Blood samples were taken on the 1st and 4th day of treatment (before starting therapy) and on the 8th day, under the same conditions. Fifteen subjects not affected by PAOD and matched for age and sex constituted the control group. ADMA was detected by HPLC with fluorimetric detection, 5-HT by HPLC with electrochemical detection. Preliminary data show a significant decrease (p<0.05) of ADMA in patients with PAOD treated with iloprost.
XVIII S.I.S.A. National Congress The relationship between BMI and common carotid plaques or Apo B and bifurcation plaques are independent of hs-CPR concentration: findings from Progetto ATENA. *G. lannuzzo, *M. Gentile, *F. Faccenda, ^F. Rubba, *A. Giannino, *S. Panico, *E. Celentano, *M. De Michete, *P. Rubba. *Dipartimento Medicina Clinica Sperimentale, Universit~l Federico II, Napoli, Italy, ^Direzione Sanitaria A.U.P., Universita Federico II, Napoli, Italy. The relationship between BMI and common carotid plaques or Apo B and bifurcation plaques has been evaluated in a population-based cohort study in women, aged 30-69, living in the metropolitan area of Naples, Southern Italy (Progetto ATENA). Serum cholesterol, HDL-cholesterol, LDL-cholesterol, Triglyceride, Insulin, HOMA, Apo B and hs-CPR are measured in 390 women, as a part of 5.062 In this group carotid ultrasound examination (B-Mode imaging) was performed in 3 sites for each artery, and prevalence at carotid sites of increased intima-media thickness IMT and/or plaque ( I M T > l m m ) was calculated. The association between IMT, BMI, Apo B and hs-CRP has been evaluated taking into account different adjustment models. Women in the second and third tertile of BMI, compared with those in the first tertile, show the following OR of having increased IMT at common carotid site: II vs I tertite 1.9 (p=0.02), III vs I tertile 2.1 (p=0.01); adjusted for age, apoB tertUes and hs-CPR. Women in the second and third tertile of Apo B, compared with those in the first tertile, show the following OR of having increased IMT at bifurcation carotid site: II vs I tertile 1.7 (p=0.05), Ill vs I tertile 2 (p=0.01); adjusted for age, BMI tertiles and hs-CPR. Hs-CPR does not contributes significantly to the models either as continuous or categoric variable. These findings show that relationship between BMI and common carotid plaques or Apo B and bifurcation plaques are independent of hs-CPR concentration.
STEROL 27-HYDROXYLASE IS REGULATED BY INFLAMMATORY STIMULI IN MONOCYTE-MACROPHAGES F. Gilardi, A. Vigil1, N. Mitro, M Crestani, D. Caruso G. Galli and E. De Fabiani Dip. Scienze Farmacologiche, Milano, Italy, 1Dep. Bioquimica, Granada, Spain There is a link between inflammation and diseases characterized by abnormal lipid storage. As modulators of lipid metabolism and immune responses, macrophages play a central rote in the atherogenic process. In macrephages sterol 27-hydroxylase (CYP27) initiates the conversion of cholesterol to more polar metabolites that are less prone to be stored within the cell. Therefore the level of CYP27 expression may have important effects on cholesterol loading and, in turn, on the inflammatory potential of macrophages. The aim of our study was to explore the role of tumor necrosis factor a (TNF--a) on CYP27 in human monocytemacrophages. We found that TNF-a induces the expression of NF-KBregulated genes and also stimulates CYP27 mRNA in PMAdifferentiated THP-I. Other genes involved in cholesterol efflux are not affected. In kinetic studies we observed that CYP27 is upregulated only after 4-24 h exposure to TNF-a. Experiments with protein synthesis inhibitors provided evidence that the mechanism by which TNF-c~ upregulates CYP27 requires newly synthesized protein factors. By transient transfections of undifferentiated THP-1, in which CYP27 is expressed at very low levels, treatment with TNF-e led to a significant but mild stimulation of the human CYP27 promoter. These results suggest that TNF-a may potentiate CYP27 expression only when the gene is already transactivated, as it occurs in mature macrophages. Our findings support the concept that CYP27 gene may be part of the inflammatory response in macrophages thus acting as a link between inflammation and lipid metabolism. A. Vigil is a fellow supported by a Marie Curie training program (EC)
15-1ipoxygenase modified LDL induce endothelial dysfunction in HUVEC A. Reduzzi, A. Pirillo, H.Kuehn, A.L. Catapano Dipartimento di Scienze Farmacologiche, Universit~ di Milano The oxidative modification of LDL contributes to atherogenesis and several evidences suggest that 15- lipoxygenase, an enzyme expressed in atherosclerotic lesions, may play a role in this process. In this work we aimed at investigating the role of 15-1ipoxygenase modified LDL (15Io/LDL) as determined by the modulation of gene transcription and protein expression during the atherogenic processes. In vitro experiments in human endothelial cells reveal that the lipoprotein modified by 15-1ipoxygenase is less associated to cells as compared to native LDL, and that this reduction is related to the extent of LDL modification (LDL =50.4%+1.04%, 15-1o/LDL 24h = 40.8%+ 4.8%,15Io/LDL 72h =17.5%+ 3.5%). In spite of their reduced ability to interact with cells, 15-1o/LDL interfere with cellular functions by modulating inflammatory mechanisms. Real time-PCR and citofluorimetry studies demonstrated that 15-1o/LDL stimulate the expression of adhesion molecules (ICAM-1) both at transcriptional and translational level, in addition incubation with 15-1o/LDL induced a higher oxidative stress in endothelial cells (%positive events:15-1o/LDL 24h= +26%,15-1o/LDL 72h= +23%, compared to native LDL). Furthermore the expression of mRNA for LOX-1, an endothelial lipoprotein receptor involved in the development of atherosclerosis, was induced after incubation with 15Io/LDL, ad demonstrated by RT-PCR (LDL =1.8+0.6, 15-LDL 24h =2.6:t:0.4, 15-LDL 72h =2.6+0.6 fold). These data suggest that 15lipoxygenase may promote atheroscleresis altering endothelial function, and underline the importance of this enzyme in inflammatory processes.
EFFECT OF ILOPROST ON PLASMA LEVELS OF SEROTONIN AND ASYMMETRICAL DIMETHYLARGININE, AND ON PLATELET LEVELS OF SEROTONIN IN PATIENTS AFFECTED BY PERIPHERAL ARTERIAL OCCLUSIVE DISEASE Blardi P. *, de Lalla A. *, Pieragalli D.*, De Franco V.*, Meini S.*, Ceccatelli L. *, Auteri A. * Centro di Farmacologia Clinica , Dipartimento di Medicina Clinica e Scienze Immunologiche, Sezione di Medicina Interna*, Universit~ degli Studi di Siena Iloprost, a stable prostacyclin analogue, is used in the treatment of peripheral arterial occlusive disease (PAOD). We investigated the effect of iloprost on peripheral markers of endothelial dysfunction, such as plasma asymmetrical dimethylarginine (ADMA) and plasma and platelet serotonin (5-HT). ADMA is an endogenous inhibitor of nitric oxide synthase, normally present in human plasma. Elevation of ADMA has been associated to impaired endothelium-dependent vasodilation and hyperaggregability of platelets. 5-HT is derived by the aminoacid trypthophan. Synthesized in enterochromaffin cells, 5-HT is released into blood, incorporated in platelets and stored in dense granules. At the site of endothelial lesions, platelets aggregate and release 5-HT that is able to induce vasoconstriction and aggregation of platelets in presence of endothelial injury and mitogenesis of arterial smooth muscle cells and endothelial cells. We investigated the effect of Uoprest on plasma levels of ADMA, as well as on plasma and platelet levels of 5-HT, in patients with PAOD (Fontaine stage III and IV). Twelve patients (9 men and 3 women, mean age 77 + 7.3 years) were included in the study. They were treated with intravenous iloprost (1.5 ng/kg/min) for 16 hours a day for 7 consecutive days. Blood samples were taken on the 1st and 4th day of treatment (before starting therapy) and on the 8th day, under the same conditions. Fifteen subjects not affected by PAOD and matched for age and sex constituted the control group. ADMA was detected by HPLC with fluorimetric detection, 5-HT by HPLC with electrochemical detection. Preliminary data show a significant decrease (p<0.05) of ADMA in patients with PAOD treated with iloprost.